Type bar actuating mechanism in standard and portable typewriters



April 23, 1940. TQMBQL|N| 2,198,520

TYPE BAR ACTUATING MECHANISM IN STANDARD AND PORTABLE TYPEWRITERS Filed Jan. 17, 1958 Even-( 01;

Patented Apr. 23, 1940 re STATES TENT orrice TYPE BAR ACTUATING MECHANISM IN STANDARD AND I WRITERS PORTABLE TYPE- Alfredo Tombolini, Milan, Italy l Application January 17, 1938, Serial No. 185,428 In Italy January 23, 1937 This invention relates to an improvement in standard and portable typewriters and more particularly it has for its object an improved and simplified type bar actuating mechanism with 'which the following advantages are ob- "mechanism and, consequently, softer and easier actuation of the key bars; elimination of the crown segment or milled bridge placed under the type bar segment, which crown segment was necessary in some typewriters for the fixing of "conjunction levers between each type bar and the corresponding pulling element; the device according to the invention permitting of the discharging of this crown segment, conserving how ever, the advantage of removing any single type bar; ((1) the possibility of giving the type bar segment a shifting movement instead of raising the carriage, to write the capital letters.

According to the invention a small conjunction plate (having a thickness of about 0.6-0.8 mm.) is provided between each type bar and the corresponding pulling element. This conjunction plate is fixed on the same segment as the type bars and is arranged either to the right or left 1 of each type bar in the slits of the segment, where the type bars are fixed.

. To provide the space for said conjunction plates it is sufiicient that the slits of the segment be of about 0.6-0.8 mm. larger.' The space for the w conjunction plate may also be obtained, as shown "in-the annexed drawing, entirely or partially, by

milling a space between each tooth of the segment, which milled space, will, of course, be shorter than the whole slit of the segment; said space might further be obtained, in the case of very thick type bars, by diminishing the thick- Fig. 1a is an end View of another conjunction plate,

Fig. 1b is a side elevational view of the plate shown in Fig. 1,

Fig. 2 is a perspective view of a part of the type bar segment,

5 Fig. 3 is a radial section of said segment,

3 Claima (Cl. 197-27) Fig.4 is a similar view showing also the conjunction plate in its position of rest,

Fig. 5 is a sectional view showing the conjunction plate in a position corresponding to the position of the key bar when depressed.

" Figs. 6 and 7 show in elevation two different forms of the type bar,

Figs. 8 and 9 are views partly in section and partly in elevation showing the type bar respectively in rest and in operative position,

Fig. 10 is a side elevational view of a modified form of a toothed conjunction plate for use in typewriters having a gear drive.

Fig. 11 is an end elevation of the plate shown in Fig. 10,

Fig. 12 is a side elevational .view of a type bar used in connection with the forms shown in Figs. 10 and 11, and

Fig. 13 is a side elevational view showing the junction plate according to Fig. 11 associated with was reached. When it was desired to remove all g of the type bars, for instance for cleaning purposes, it was necessary to disengage them from the pulling elements which latter were left inside the machine. These elements often became loose also at the opposite end and fell inside of the machine causing much trouble and inconvenience, especially when said pulling elements were of different length and shape. Said'inconveniences have been tolerated up to now for the following reasons: (a) in portable machines, because in view of the lowness of this kind of typewriter, there was no space under the type bar segment to arrange the crown segment; (11) in standard typewriters, because actually the actuation of the key bars is easier, allowing greater writing speed with less fatigue when the type bars are directly connected with the pulling element, without the intermediary levers. But this system did not permit the removal of the type bars singly from the type bar segment. This is, however, a necessary feature in typewriters both for the typist, the repairer and the manufacturer, when assembling the typewriters, for the operations of so1dering and arranging the letters on the heads of the type bars.

Up to now, to obtain this result, in some standard typewriters, where a sufiicient space existsbut not in portable machinesa crown segment or milled bridge is arranged under the type bar segment; on said crown segment conjunction levers are fixed which connect the type bars with the pulling elements.

But the arrangement of conjunction levers in a crown segment gives rise to a great inconvenience as said conjunction levers describe such a movement that the fixing journal of the conjunction lever (sliding in the oval shaped slit of the type bars) gets too near to the point of fullcrum of the type itself and, owing to" the gradually greater resistance which ensues, the; keys gradually become stiffer, and cause loss. of time in operating, imperfect impression of the letters,

unsatisfactory multiple copies, etc.

' a On a standard? typewriter an attempt has been made toremedy this by means of a double open slit on the type bar andrelativedouble pin onthe connecting lever; this is but a partial and not a thorough improvement which, anyway, makes it necessary to maintain the crown segment under the type bar segment.

The contrivance forming the object of this invention maintains all the advantages offered by the rod following the trajectory of the type bar and toothed sector and remedies the entire situation in that it permits the removal of single type bars, does away with the crown segment or milled bridge placed under the type bar segment and, moreover, allows those typewriters that are without it, to write capital letters, by displacing or shifting the type bar segment instead of the carriage, which constitutes an advantage especially as regards machines fitted with a long carriage.

With reference to the annexed drawing: A indicates the conjunction plate placed between type bars and pullingelements; B indicates the toothed segment between whose teeth I, are pivoted the above mentioned plates, being provided, for thisv purpose, with bores or openings I. The plates are further provided with a small pin 4 on which rests the fork ID or hook iii of the typev bars, and are provided with a bore 2 to which the rods or pulling elements 8' are hooked. C indicates the toothed conjunction plate as, used in typewriters having a gear drive.

. Arranged in the bore or opening I of the conjunction plate A is the semi-circular axis of segment 5 (Figs. 3, 4) Arranged in the opening 2 is the rod 8 (which previously was introduced into the bore of the type bar directly). 3'designates a headed pin, behindwhich is to-be placed circular bar (Figs. 8, 9, 13).

head as shown at 4. Fig. 11 shows the same plate, as conceived, but toothed, intended for the portable typewriters in which, instead of the rod, the 'motion of the type bar is of the so-called Franklin gear system, which however, up to now has not permitted the removal of a single type bar at a time.

Arranged in the sectioned. segment B is the semi-circular axis 5 into which are introduced the connecting plates and on which are hooked the type bars. The sides of the teeth 1 are recessed as by milling at 6 so as to contain, besides the type banalso the conjunction plate A.

In Fig. 7: there is shown another conformation that the type. bar may have, in case it should be necessary to increase the length of the'conjunction plate through the fastening bore of rod 8, or by applying on the reverse face of the plate a fastening for said rod.

In Figs. 10 to 13 there is shown a modified form of the invention adapted. for use on typewriters having a. gear drive. The conjunction plate C is in the form of a toothed segment; having.

an opening. I t for mounting on axis :5 and is fitted with a pin l2 for receivingthe fork l3 on the junction plate C to rockthe latter when desired I to operate the typeloar l3.

To remove and replace the type bars one proceedsin the usual way followed with typewriters,

that is to say by removing the common semi- It is, understood thatzthe particulars of construction and shape may inpractice vary, withand having a supporting pin and a type. bar having a double hooked end also arranged inv said groovev and engaged with the semi-circular axis and with the supporting pin of the con.- junction plate.

2. Improvement as claimed in claim '1 wherein.

a rod is provided for pivoted connection with the lower end of the conjunction plate.

3. Improvement as claimed in claim I, applied on a typewriter having a gear drive for the type bar, in which the conjunction plate has a toothed sector for the gear drive of the type bar.

ALFREDO TOMBOLINI. 

